Sintering Mechanism of Vapor Self-Assembled Multilayer (VSAM) Coated Cu Nano Particles for Application in Cu Nano Ink

Abstract

Oxidation preventive Cu nano ink was prepared using a vapor self-assembly multi-layer coating method (VSAMs). These particles were prepared using 100 nm Cu nano particles coated with 1-octanethiol under an ultrahigh vacuum condition with octanol used as a solvent. Octanol-based non-oxidized 10% (wt.) nano ink was well-dispersed without any surfactant. The conductive ink had good dispersion and remains stable for more than weeks. It also has a low viscosity rating of 8.3 cPs. In addition, 5 μL of copper nano ink was dropped into a 1 cm x 1 cm glass substrate to form a copper pattern. The copper pattern was then sintered at 350°C in a tube furnace in a H2 gas atmosphere. The resistivity of the film using the fabricated ink was determined to be 5.8 × 10^(−6) Ωcm. The results show that the non-oxidized oxidation-preventive copper nano ink is suitable for ink-jet printing.